As a wide band gap semiconductor, gallium nitride (GaN) has high breakdown voltage, excellent structural stability and mechanical properties, giving it unique advantages in applications such as high ...frequency, high power, and high temperature. As a result, it has broad application prospects in optoelectronics and microelectronics. However, the lack of high‐quality, large‐size GaN crystal substrates severely limit the improvement of electronic device performance. To solve this problem, liquid phase growth of GaN has attracted much attention because it can produce higher quality GaN crystals compared to traditional vapor phase growth methods. This review introduces two main methods of liquid phase growth of GaN: the flux method and ammonothermal method, as well as their advantages and challenges. It reviews the research history and recent advances of these two methods, including the effects of different solvents and mineralizers on the growth quality and performance of GaN crystals, as well as various technical improvements. This review aims to outline the principles, characteristics, and development trends of liquid phase growth of GaN, to provide more inspiration for future research on liquid phase growth, and to achieve further breakthroughs in its development and commercial application.
The flux and ammonothermal methods are capable of the growth of large size, high quality GaN crystals, which are the main methods of liquid phase growth. The research progress of these two growth methods in terms of chemical additives and growth process is summarised, and their application prospects in industrial production are discussed.
With the energy crisis and environmental pollution, the development of sustainable new energy has become an urgent priority. These considerations make society aware that green energy technologies are ...critical to economic development. Electrochemical energy storage technology is a green energy technology based on the ability to exhibit high energy density (battery) or high power density (supercapacitor). There is a growing demand for high-energy and high-power-density electrochemical energy storage devices for current and future applications. However, the performance of electrochemical energy storage devices is limited by the activity of electrode materials. It is difficult to meet the demands of rapid economic development for energy equipment with high energy density, high power density and long life. The energy density of supercapacitors can be significantly improved by preparing novel active electrode materials. Research has found that new semiconductor materials have the potential to improve the cycle life, energy and power density of supercapacitors. To date, a variety of novel semiconductor electrode materials have been fabricated and studied for supercapacitors. This review summarizes the main advantages of several new semiconductor materials as electrode materials. In addition, the latest and representative progress in the development of electrode materials for supercapacitors is presented. Finally, current challenges are discussed and key perspectives for future research in this field are outlined.
This manuscript systematically reviews the research progress of novel semiconductor materials in the preparation and application of SCs.
As the wide band gap, extreme mechanical hardness and high thermal conductivity, GaN has found widespread applications in optoelectronic devices and high-power/frequency devices. However, the growth ...of high-quality and large-size GaN crystal substrates still a great challenge, which barrier to the development of power and radio frequency (RF) devices. Na-Flux method could emerge as an effective strategy to address these challenges. Nevertheless, the growth quality of GaN crystals was influenced by several factors during the growth process. This study focused on investigating the growth rate and quality of GaN in relation to growth temperature and pressure. It also explains the difference in solubility between N3- and GaN as a function of temperature in liquid phase melts. The intricacy of the Na-Flux method and the opacity of the growth process present significant obstacles to the growth of GaN crystals. In order to accurately determine and optimise the growth conditions, the temperature distribution and material transport during the growth process are predicted by simulation. A series of validation experiments were conducted to investigate the influence of temperature and pressure on GaN crystallisation. Under the optimised growth conditions, high-quality GaN crystals with a full width at half maximum of 433 arcsec (002) were obtained. This work provides an effective strategy for the liquid-phase growth of high-quality GaN crystals, facilitating the development of high-performance blue-green lasers, RF and power devices.
Owing to its wide band gap, extreme mechanical hardness and high thermal conductivity, GaN has found widespread applications in optoelectronic devices and high-power/-frequency devices. However, the ...growth of high-quality and large-size GaN crystal substrates is still a great challenge, which hinders the development of power and radio frequency (RF) devices. The Na-flux method can emerge as an effective strategy to address these challenges. Nevertheless, the growth quality of GaN crystals is influenced by several factors during the growth process. This study focused on investigating the growth rate and quality of GaN in relation to the growth temperature and pressure. It also explains the difference in the solubility between N
3−
and GaN as a function of temperature in liquid phase melts. The intricacy of the Na-flux method and the opacity of the growth process present significant obstacles to the growth of GaN crystals. In order to accurately determine and optimise the growth conditions, the temperature distribution and material transport during the growth process are predicted by simulation. A series of validation experiments were conducted to investigate the influence of temperature and pressure on GaN crystallisation. Under optimised growth conditions, high-quality GaN crystals with a full width at half maximum of 433 arcsec (002) were obtained. This work provides an effective strategy for the liquid-phase growth of high-quality GaN crystals, facilitating the development of high-performance blue-green lasers, RF and power devices.
GaN single crystals (15 × 15 mm) were epitaxially grown using the Na-flux method, and substrate self-peeling was achieved. The effect of temperature and pressure on the growth rate and the quality of GaN single crystals are investigated.
Owing to its wide band gap, extreme mechanical hardness and high thermal conductivity, GaN has found widespread applications in optoelectronic devices and high-power/-frequency devices. However, the ...growth of high-quality and large-size GaN crystal substrates is still a great challenge, which hinders the development of power and radio frequency (RF) devices. The Na-flux method can emerge as an effective strategy to address these challenges. Nevertheless, the growth quality of GaN crystals is influenced by several factors during the growth process. This study focused on investigating the growth rate and quality of GaN in relation to the growth temperature and pressure. It also explains the difference in the solubility between N3− and GaN as a function of temperature in liquid phase melts. The intricacy of the Na-flux method and the opacity of the growth process present significant obstacles to the growth of GaN crystals. In order to accurately determine and optimise the growth conditions, the temperature distribution and material transport during the growth process are predicted by simulation. A series of validation experiments were conducted to investigate the influence of temperature and pressure on GaN crystallisation. Under optimised growth conditions, high-quality GaN crystals with a full width at half maximum of 433 arcsec (002) were obtained. This work provides an effective strategy for the liquid-phase growth of high-quality GaN crystals, facilitating the development of high-performance blue-green lasers, RF and power devices.
The plastics structure–property correspondence has been conventionally identified through either a forward discovery chemistry approach or a reverse analysis physics approach. The viewing of each ...monomer unit as a nondivisible entity limits these approaches as an inherently nonprogrammable tool. Herein, molecular plastics programming is reported as an effective prescriptive strategy for achieving programmable molecular, macroscopic correspondence. With each monomer envisioned as a divisible entity constituted with building blocks (rigid, flexible, spacer coupling, linker), a set of guiding principles has been established for the predictive mapping of the polymer chain architecture to physical properties (thermal, mechanical, brittle, or ductile). Polymer main-chain rigid-flexible-building-block coupling is established as a feasible route toward mechanical activation and therefore ductility. Squaramide has been utilized as a building block for the design and synthesis of an amorphous-phase, ductile, and degradable plastic, showcasing molecular plastics programming as a promising platform for precision plastics engineering and sustainable polymer development.
One of the most important factors for the future application of circularly polarized luminescence (CPL) materials is their high dissymmetry factors (g em), and more and more studies are working ...tirelessly to focus on increasing the g em value. Herein, we chose an achiral liquid crystal polymer (LC-P) and two chiral binaphthyl-based inducers (R/S-3 and R/S-6) with different substitution positions (3,3′ positions for R/S-3 and 6,6′ positions for R/S-6) to construct chiral co-assemblies and explored their induced amplification CPL behaviors. Interestingly, after the thermal annealing treatment, this kind of chiral co-assembly (R/S-3)0.05–(LC-P)0.95 can emit a superior CPL signal (|g em| = 0.31 and λem = 424 nm), which achieves about 13-fold signal amplification in the spin-coated film, compared to (R/S-6)0.1–(LC-P)0.9 (|g em| = 0.023 and λem = 424 nm). This is because (R/S-3)0.05–(LC-P)0.95 could further co-assemble to form a more ordered arrangement LC state and generate regular helix nanofibers than that of (R/S-6)0.1–(LC-P)0.9. This work provides an efficient method for synthesizing high-quality CPL-active materials through the strategic manipulation of the structure of chiral binaphthyl-based inducers in chiral co-assembled LCP systems.
Several international centers have used and reported pediatric-inspired regimens for adolescent and adult patients with Philadelphia chromosome-negative acute lymphoblastic leukemia (Ph- ALL). ...However, there is a lack of prospective data on the Chinese population. Herein, we performed a prospective study with a pediatric-inspired regimen (IH-2014 regimen) in treating adolescent and adult Ph- ALL patients in our center. From 2014 to 2021, a total of 415 patients aged between 14 and 65 years (median age, 27) were included in this study. After a median follow-up of 40.8 months, the 5-year overall survival, disease-free survival, and event-free survival rates were 53.8%, 51.1% and 45.0%, respectively. The regimen was generally well tolerated and safe, and the overall chemotherapy-related mortality was 3.6%. Age ≥ 40 years and persistent detectable minimal residual disease (MRD) post-induction were independent prognostic factors. Traditional risk factors for adult patients combined with MRD post-induction exhibit predictive significance for survival and relapse, which is helpful in the selection of subsequent treatment. Patients with high risk factors who can achieve deep MRD response after induction do not derive benefit from allogeneic hematopoietic stem cell transplantation.
The design of excellent circularly polarized luminescence (CPL) materials with a large luminescence dissymmetry factor (g lum) remains a great challenge. In this paper, we chose two achiral ...conjugated pyrene-based main-chain polymers (BP-1 and BP-2) with different substitution positions (1,6-positions of the pyrene rings for BP-1 and 2,7-positions of the pyrene rings for BP-2) and a chiral binaphthyl-based inducer (S/R -D) with a bridged alkyl chain to construct chiral coassemblies through an intermolecular chirality induction mechanism. Interestingly, after the thermal annealing treatment, the resulting coassemblies S/R -D-BP-2 could emit inverted and amplified CPL signals compared with S/R -D-BP-1. Most significantly, the maximum |g lum| value of (S/R -D) 0.2 -(BP-2) 0.8 in a spin-coated film was up to 0.71 (λem = 428 nm, QY = 44.8%) at a 220 nm thickness, which was about 6-fold that of (S/R -D) 0.1 -(BP-1) 0.9 (|g lum| = 0.12, λem = 451 nm, QY = 37.6%). The excellent g lum value of (S/R -D) 0.2 -(BP-2) 0.8 was due to the formation of regular and ordered helical nanofibers through the strong intermolecular π–π stacking interactions. This work provides a creative approach to tune the CPL emission amplification behaviors by chiral coassembly from achiral pyrene-based main-chain polymers.
Coronary heart disease (CHD) is one of the leading causes of deaths globally. Identification of serum metabolic biomarkers for its early diagnosis is thus much desirable. Serum samples were collected ...from healthy controls (
= 86) and patients with CHD (
= 166) and subjected to untargeted and targeted metabolomics analyses. Subsequently, potential biomarkers were detected and screened, and a clinical model was developed for diagnosing CHD. Four dysregulated metabolites, namely PC(17:0/0:0), oxyneurine, acetylcarnitine, and isoundecylic acid, were identified. Isoundecylic acid was not found in Human Metabolome Database, so we could not validate differences in its relative abundance levels. Further, the clinical model combining serum oxyneurine, triglyceride, and weight was found to be more robust than that based on PC(17:0/0:0), oxyneurine, and acetylcarnitine (AUC = 0.731
0.579, sensitivity = 83.0
75.5%, and specificity = 64.0
46.5%). Our findings indicated that serum metabolomics is an effective method to identify differential metabolites and that serum oxyneurine, triglyceride, and weight appear to be promising biomarkers for the early diagnosis of CHD.
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